Pneumatic stapler and magazine therefor



July 3, 1962 M. P. DHAEM ETAL 3,0

PNEUMATIC STAPLER AND MAGAZINE THEREFOR 3 Sheets-Sheet 1 Filed May 10, 1960 uvwvrons MARCEL P. DHAEM HOWARD R. FISCHER W ATTORNEY July 3, 1962 M. P. DHAEM ETAL 3,

PNEUMATIC STAPLER AND MAGAZINE THEREFOR 3 Sheets-Sheet 2 Filed May 10, 1960 I: III illi!!! 1 a m V 2 v 2 A TTORNE Y July 3, 1962 M. P. D'HAEM ETAL 3,041,614

PNEUMATIC STAPLER AND MAGAZINE THEREFOR Filed May 10, 1960 s Sheets-Sheet s A TTORNE Y R -19? M4 QM mm J NM WEN mm L m a mm I 6 an R ofl mmm m; -l- \wm MH 3 Y @N PS B a ON k *WJN MN MS g 3 mm ME 1; ym "x mm 2: mm

3,041,614 PNEUMATIC STAPLER AND MAGAZINE TIERIJFOR Marcel I. DHaem and Howard R. Fischer, Utica, NY,

assignors to Chicago Pneumatic Tool Company, New

York, N.Y., a corporation of New Jersey Filed May 10, 1960, Ser. No. 28,115 12 Claims. (Cl. 1-44.4

This invention relates to a pneumatic stapler and more particularly to a magazine therefor.

It is the principal object of the present invention to provide a stapler with a magazine which permits the return of the staple follower rod to its locked position before loading the staples into the magazine and release of the follower.

It is another object of the invention to provide in a stapler a staple magazine in which the magazine staple loading door is automatically opened with the retraction of the staple follower.

It is still another object of the invention to provide in a staple magazine to which access is had through a door, means wherein the staple follower is automatically released when the door is closed.

It is a further object of the invention to provide a stapler that has a removable staple guide cover that perrnits quick and easy access to the area where the jamming of the staples is most likely to occur.

't is a still further object of the invention to provide in a stapler having a removable staple guide cover a safety brake device automatically engageable with the staples in the magazine as the guide cover is removed to prevent the staples from being shot through the staple discharge opening in the end of the magazine even with the full follower spring pressure being exerted against the staple strip within the magazine.

Other objects of the invention are to provide a pneumatic stapler having the above objects in mind which is of simple construction, has a minimum number of parts, easy to fill and refill with staples, compact, that can be operated without jamming, efficient and effective in use.

For a better understanding of the invention, reference may be had to the following detailed description taken in connection with the accompanying drawing, in which FIGURE 1 is a longitudinal sectional view of the pneumatic stapler embodying the features of the present in vention,

FIG. 2 is a fragmentary side elevational view of the lower end of the stapler looking upon one side of the staple magazine,

FIG. 3 is a fragmentary horizontal sectional view of the stapler taken on line 3-3 of FIG. 1 looking upon the top of the staple magazine, the cover being broken away to look into the interior thereof,

FIG. 4 is a vertical sectional view of the stapler taken on line 4-4 of FIG. 3 and looking in elevation upon the magazine and with parts thereof broken away to better show the construction thereof, the follower engaging the staples to force them forwardly,

FIG. 5 is a vertical sectional view similar to FIG. 4 with the follower having been retracted its full rearward extent by the follower rod and the magazine door released from the forward lip,

FIG. 6 is a transverse sectional view of the staple magazine as viewed on line 6-6 of FIG. 4 and looking rearwardly therefrom in the direction of the arrows thereof with the magazine top cover being closed,

FIG. 7 is a similar transverse sectional view of the staple magazine as viewed on line 7--7 of FIG. 4 and looking forwardly therefrom in the direction of the arrows thereof,

3,41,6l4 Patented July 3, 1962 FIG. 8 is a transverse sectional view similarto FIG. 7

as viewed on line 88 of FIG. 5 but with the magazine top cover being elevated and its lug projected into the follower to lock the follower in its fully retracted position, f

FIG. 9 is a fragmentary lower front face elevational view of the stapler,

FIG. 10 is a fragmentary vertical sectional view of the forward lower end of the stapler as viewed on line 10-40 of FIG. 9,

FIG. 11 is a fragmentary vertical sectional view of the forward end of the stapler as viewed on line 11-11 of FIG. 10 and with the staple guide cover plate removed to expose the magazine guide plate and the discharge opening thereof, and staples in the magazine,

FIG. 12 is a fragmentary vertical sectional view as viewed on line 1212 of FIG. 10 and looking in elevation upon the staple brake device,

FIG. 13 is a fragmentary longitudinal sectional view of the forward end of the stapler as viewed on line 13-13 of FIG. 11. with the guide cover in place and the staple brake device retracted,

FIG. 14 is a fragmentary vertical sectional view of the forward end of the stapler similar to FIG. 13 but with the vertically-extending staple guide cover removed and the staple brake device released to its braking position in engagement with the staples to restrain the same from being shot through the discharge opening of the magazine, and

FIG. 15 is an exploded perspective view of the forward discharge end parts of the stapler.

Referring now particularly to FIG. 1, 20 represents a handle body formed of a single casting having a hand grip portion 21, a vertically-extending cylinder portion 22 forwardly thereof and a depending rear leg magazine-supporting portion 23. The hand grip portion 21 has a 1 threaded air inlet opening 24 and an air expansion chamher 25 in which the air is stored under pressure. An air pressure hose is connected to the inlet opening 24 by any suitable hose fitting so that the air expansion chamber 25 is supplied with air and is thereby maintained at all times at the pressure of the air supply system. Intermediate the expansion chamber 25 and the vertically-extending cylinder portion 22 is ,a similarlyeextending valve opening 26 aligned with a port 27 leading from the expansion chamber 25 so that air may be supplied there-v from to change the valve opening '26.

Within the valve opening 26 is a tight-fitted valve bushing 28 that itself .has a valve chamber 29 in which a lift valve 30 operates. This lift valve 30 seats upon the upper end of the valve bushing 28 and when lifted will allow the air to pass from the air expansion chamber 25 past the valve 30, the valve bushing chamber 29 and through a passage 31 into the vertically-extending cylin- 20 by a pin '34. This trigger 33 is located under the hand grip portion 21 so that it can be pulled by the trigger finger of the hand whilegrasping the hand grip portion 21. The pulling of the trigger is made against the action of a compression spring 35 that is contained in an enclosure cap 36 threaded into the upper end of the valve opening 26. The valve 30 is kept in its closed position by the compression spring 35 and the pressure from the expansion chamber 25, and is only lifted when the trigger 33 is pulled. a

The valve bushing 28 has. an exhaust port 37 leading from its chamber 29 to an exhaust passage 38 extending through the hand grip portion 21 and running parallel to the air chamber 25. As the trigger 33 is squeezed, the

7 valve 30' is lifted and the val-ve'stem extension-'32; closes the exhaust port 37in the valve bushing 28. The valve 30 is lifted from its seat, air at line pressure passes through the valve buushing chamber 29 and into the passage 31 to a cylindrical chamber 39 and abouta piston 40 operable therein. This air leaks around the upper end of the piston 40 and pressure is built up about the top of the piston under a threaded cap 4-2: in the upper end thereof,

so that the piston is thrust downwardly to perform the work operation. The lower end of the piston chamber 39 is vented by a vent plug 41. The passage 31 leads to the 'upper end of the cylindrical chamber 39, and when t-he' piston is completely exposed, the piston moves downwardly rapidly carrying with it a blade-carrying head 43 held within the piston 40, the piston beingheld against the cap 42 by a long compression piston return spring 44 extending upwardly from a reduced diameter bottom portion 45 of the cylindrical chamber 39f and from which the air vent plug 41 extends. A small disc 45 supports the spring 44 in the bottom portion 45- and helps to guide substantially that of the thickness and width of the staple.

A vertically-extending guide cover plate '51 is provided with a guide way '52 in which the blade 46 travels to strip off an advanced staple of a series or strip of staples 53 extending from a staple magazine assembly 54 supported between the lower ends of the handle cylindrical portion 22 and the'depending leg portion 23. The construction and operation ofthe magazine will be later described.

' Thestaple is pushed downwardly through the guide cover and driven into the work W from the lower end thereof. The stroke of the'piston 40 ends when it engages and compresses an annular rubber bumper 55 in the lower end of the cylindrical chamber 39 through which the compression spring 44.and the blade 46 extend.

The force of the blade serving to drive the staple is 62 is made secure to the base by three fastening screws 63, 64 and '65 longitudinally-spaced from one another with flat heads extending into and made flush with the underface of the track, base 60. The width of the track 62, is such that cohered strips of staples 53 straddle the track and are freely slida'ble thereover, The height of the track 6 2 exceeds the leg length of the longest staple to be used in the tool.

A staple follower 67 straddles the track 62 and pushes the strip of staples 53 toward the front of the tool. This staple follower 67 has a depending bracket 68 with a hole therein through which a follower rod 69 is slidable. The forward end of the follower rod 69 has an enlarged integral head 70 that engages with the depending bracket 68 so that the follower 67 can be pulled by the rod 69 rearwardly. The follower 67 pushes the strip of staples toward the front of the tool over the staple track 62. A follower spring 71 surrounds the follower rod 69 and provides a forward thrust upon the staple follower 67.

The follower rod 69 passes through a hole in a rear block 72 at the rear end of the magazine track base 60 and into which the securing bolt 59 extends to secure magazine 54 to the offset portion 58 of the handle rear leg 23. The follower rod 6-9 has a knob 73 fixed to its rear end by a pin 74. The follower rod 69 is normally held in its forward position by an O-ring 75 which engages with an annular groove 76 on the follower rod. Anend cap 77 is held the rear end block 72 against the 0- ring 75 by the follower spring 71 and in turn serves to hold the O-ring in place within the rear end block 72.

A hinge plate 78 is secured by screws 79, FIG. 2, to the right side of the track base 60 and supports a hinge pin 80 on which a magazine top cover 81 is hinged and slidably adjustable. A spring 82 surrounds the hinge pin 80 at its forward end and is stressed in torsion and compression when the cover 81 is closed. The torsional force of this spring tends to open the magazine cover 81 while the compressive force thereof upon reacting against a hinge cover portion 83 from the hinge plate 78 holds the controlled by the size of the orifice in the vent plug 41 p and the dept-hthe staple driven is controlled either by varying thelength of the driving blade 46 or the height 'pf therubber bumper 55. At the end of the driving stroke thegpiston 40 remains in contact with the rubber bumper'SSj with the full line air-pressure against its top surface area. -When.the trigger 3*3is released the valve 30 is forced down against its seat on the upper end of thev bushing 28 by the valve spring 35. Thedownward'move flmeut of the valve stem extension 32 exposes the bushingenhaust port'3-7 to the valve chamber 29 so that the air trapped above the piston may be exhaustedthrough the passage 31, bushing chamber 29, port 3-7 and to the atmosphere through exhaust passage 38 extending to the rear end of the hand grip portion 21.

magazine cover 81 forward so that it engages a lip 84 of a front block 85 to lock the magazine cover in its closed position. The magazine cover 81 carries a runner plate 86 on its underface that serves to keep the strip of staples 53 upon the track 62.

Fixed to the forward end of the track base 69', is a vertically-extending guide plate 88 that has a rectangular staple discharge hole 89 that is slightly higher and wider than the overall height and Width of the staple to be driven. The upstanding sides of the track base 60 have threaded holes 90, 91, FIG. 15, for respectively receiving screws 92, 93- extended through countersunk open- 1 ings 94-, 95 of the vertically-extending guide plate 88 .rests over the edge of the forward block 85 that is se- The pistonxlfi is returned upwardly by its spring 44 and 1 to a point Where the upper end of the passage 31 is cov- V ered. The trapped air above the piston 40' serves as a cushion and is gradually exhausted .therearound until the piston contacts the cylinder capv 42 so that it is then made ready for the next driving cycle. f v V The forward end of the staple magazine 54 is made swure to the vertically-extending cylinder portion 22 of the handle body casting 22 by two. laterally-spaced bolts 56' and 57 extending. through the magazine and threaded into the lower end of the cylinder portion 22 FIGS. 1; 3, 4 and i 10.7,,The rear end of the magazine 54 made secure to an ofi'set lower end portion 58 on the depending rear leg j P 23 ofthe handle casting 20 by alateral-ly-extendig secur-j fing-bolt.59.FI GS.,l aud2. j W f-- 'I'hestaple magazine 54 has a track base of U-shaped section with an internal 'mou'nting groove 61 running therethrough for the mounting of a staple track 62 that extends. and projects upwardly therewithin. The track' cured to the handle cylinder portion 22 by two upwardlyextending fastening screw bolts 97 and 98, FIGS. 3, 4 and 5. The rectangular discharge hole 89 in the guide plate 88 is aligned with the staple track 62 which has spaced forwardly-extending projections 99 and 100 that extendthereinto. The staples 53 ride these projections through the discharge hole 89 to the point where they leave the trackand are picked up by the driving blade 46. The guide plate 83 can thus be easily removed by removing screws 92'and 93, and replaced by similar plates to provide different discharge holes in order to accommodate different leg length staples. Thehandle cylinder portion 22 has a transverse slot 101 that receives the guide plate 88 and the guide cover 51 that is supported on two laterally-spaced lugs 102, 103 on the forward faceof the guide plate 88 having respectively upwardly and forwardly beveled retaining faces 104, that receive respectively beveled edges 166, 107 of the guide cover 51, FIG, 15. The blade guide cover 51 has :1 depending extension 108 that lies between the lugs 1&2, 193 of the guide plate 88 and the guideway 52 extends vertically throughout the full inner face of the guide cover plate 51 including the depending extension 168 and through which the blade 46 slides and the staple 53 is extended. The guide cover 51 is held elevated in the handle transverse slot 101 by two inclined set screws 109, 110 that are accessible from the front of the handle cylinder portion 22 and which respectively engage with respective indentations 111 and 112 on the front face of the cover plate 51. To remove the guide cover 51, the set screws 109, 110 are released from the cover indentations and the cover 51 is pushed upwardly and with sufiicient looseness in the slot 161 so that its lower end can be pulled out to disengage its beveled edges 106, 107 from the guide plate lug faces 1M, 1135 and thereafter the guide cover 51 can be withdrawn downwardly out of the slot 1111 and from the handle casting cylinder portion 22. By this construction quick and easy access is provided to that part of the tool where jamming 0f the staple is most likely to occur. The width of the guideway 52 is slightly greater than the width of the staples 53.

To. insert a strip of cohered staples 53, the follower knob 73 and its rod 69 are pulled rearwardly from the O-ring 75 so that the follower 67 by its depending bracket compresses its follower spring 71. When the rear edge of the follower contacts a rolled under lip 115 on the rear end of the bottom runner plate 86 of the magazine cover 81 as shown in FIG. 5, the entire cover 81 is moved rearwardly a fraction of an inch to compress its combined torsion and compression spring 82 so that the front edge of the cover 81 is freed from the lip 84 of the front block 85. The torsion in the cover spring 83 causes the cover to be automatically opened and its inwardly curved lug 116 to be rotated into a slot 117 in the follower 67. This locks the follower 67 in its rearward position against the full pressure of the follower spring 71 tending to move the follower forwardly. The follower rod 69 and its knob 73 is then pushed forwardly to its original position and slidable through the hole in the follower bracket 63 until the annular groove 76 in the follower rod 69 receives the O-ring 75 so that the follower rod is by this means held forwardly.

With the magazine cover 81 open and the follower 67 retained by the cover in its retracted position by the cover, the follower rod 6% may be returned to its forward position. A strip of cohered staples 53 can be dropped into the magazine so as to straddle the upstanding sides of the staple track. After inserting the staples 53, the magazine cover 81 is closed against the torsional resistance of the hinge pin spring 82 and when the cover is flush against the track base 6% the compressive force of the hinge spring 82 forces the cover forwardly so that its forward edge seats under the lip 84 of the forward block 85 to thereby lock the cover closed.

Upon so closing the cover the curved depending lug 116 of the cover is automatically withdrawn from engagement with the follower 67 and out of the slot thereof permitting the follower spring to move the follower forwardly until the front edge of the follower 67 contacts the rearmost staple of the staple strip. The pressure from the follower spring 71 is transmitted through the follower to the staple strip and forces the forwardmost staple through the discharge hole 89 in the guide plate and into the guideway 52 of the guide cover 51 so that this first staple is located directly under the driving blade 46. Thus, when the trigger 31 is pulled, the first staple 53 will be sheared from the strip of staples by the driving blade 46 and driven home into the work piece W, FIG. 4.

The stapler follower 67 always feeds the staples 53 toward the front of the magazine except when the follower 67 is locked in its retracted position. If the forward guide cover 51 is removed and there are staples still in the magazine, a dangerous situation is presented as the staples are apt to be shot out of the magazine through the discharge hole 89 in the magazine guide plate 88. Since the guide cover 51'is removed in the manner above explained the possibility of the release of the staples is minimized. In this manner the guide cover 51 has to be pushed upwardly in the transverse slot 101 to release the bevel edges 106 and 1&7 from the lugs 102'and 103 of the magazine guide plate 88,

and instead of the staples 53 being forced through the discharge opening 89 of the guide plate 88, they apply pressure against the guide cover plate 51 and tend to force its lower end outwardly, and wedging the cover plate 51 in the transverse slot 101. The operator is alerted that relief of pressure is necessary and that the follower 67 has to be retracted to its locked position. This will automatically open the magazine cover 81 so that the condition of the staples within the magazine can be observed at this time.

To overcome the jamming of the staples and this situation, there has been provided a positive safety device to prevent the forward motion of the staples 53 even if the pressure upon the staples has not been relieved or the follower 67 retracted. The forward block 85, which is located between the staple magazine 54 and the handle casting 20, has a horizontal slot 118 in which rides a staple brake 119 and has stop shoulders 118' on which the brake ends rest. The lower end surface of the staple brake 119 is serrated at 120 to grip the staples 53. Normally, the staple brake 119 rides freely on top of the staple strip allowing the staples to pass beneath it.

A pair of plungers 121 are respectively disposed in blind holes 122 directly above the staple brake 119. The plungers 121 are forced downwardly by springs 123 but are prevented from contacting the staple brake 119 by a pair of plunger retractors 124 which have tapered heads 125 that are held in V-shaped annular grooves 126 in the plungers 121 by the cover guide 51.

When the'guide cover 51 is removed, the retractors 124 are free to move away from the plungers 121 so that the plungers force down the brake 119 by the springs 1123 and then the brake wedges against the top of the staple strip thereafter preventing the forward motion of the staples 53. When the staple guide cover-is replaced, the retractors are moved inwardly toward the plunger 121, further seating them in the V-shaped grooves 126 and raising the plungers 121 thereby freeing the brake 119 so that its serrated end may again ride the staples 53.

It should now be apparent that there has been provided a magazine for' a pneumatic stapler which is automatically operated by the retraction of the follower to open the magazine door and wherein the follower in its retracted position is locked by the door lug and is automatically released as the magazine door is closed. Also, it should be apparent that the follower rod that serves to retract the follower can be returned to its forward position prior to the release of the follower.

'It should further be apparent that there has been provided in a pneumatic stapler a brake device that will automatically prevent the shooting of the staples from the stapler upon the vertically-extending guide cover plate being removed from the stapler to overcome a jam of staples and at the same time giving warning to the operator' that the follower should be retracted and the magazine door should be opento observe thefull cause of the staple jam and the release of the staple effected and wherein automatically the staple brake device is released I as the staple guide cover is returned to'the stapler.

While various changes may be made in the detailed construction, it shall be understood that such changes shall be within the spirit and scope of the present invention as defined by the appended claims.

'What is claimed is:

1. Amagazine for discharging staples, comprising a track for slidably supporting the staples, a magazine track base, a magazine cover hinged to one side of the magazine track base and being longitudinally movable between locked and released positions with and from. the

the cover from its engagement with the forward end of the magazine whereby the cover will be automatically opened under the action of its spring upon the retraction of the follower.

.2. A magazine for discharging staples, comprising a;

track for slidably supporting the staples, a magazine track base, a cover hinged to one side of the magazine track base and being longitudinally movable between locked and released positions with and from the forward end of the magazine, spring means biasing said cover toward the forward end of the magazine and into locking engagement therewith and when retracted therefrom serving to open the cover, a staple follower overlying the track, a follower pull rod connected to the follower to pull the follower rearwardly, said follower being retractable to the rear end of the magazine and engageable with the cover when being retracted thereto to move the cover rearwardly against the spring bias to 'free the cover from its engagement with the forward end of the magazine whereby the cover will be'automatically opened under the action of its spring upon the retraction of the follower, said hinged cover having aspart-engageable with said follower to hold thefollower in its retracted position when'the'cover is open. 1 i

3. A magazine for discharging staples, comprising a body and a track for slidably supporting the staples, a cover hinged to one side of the body and being longitudinally movable between locked and released positions with and from the forward dischange end of the magazine,

spring means biasing said cover toward the forward" end of the magazine into locking engagement therewith'and a 8' automatically opened under the action of its spring upon the retraction of the follower, said hinged cover upon being opened having a part that is engageable with said follower to hold the follower in its retracted position and atfollower spring normally biasing/the follower toward the forward discharge end of the magazine, said follower pull rod being slidable through the follower to permit the return of the follower pull rod to its forward position without the follower, and said magazine having a hole in the rear end thereof and an O-ring retained in said hole through which the follower pull rod is slidable and by which it is retained in its forward position free of the follower.

5. A magazine for discharging staples, comprising a body and a track for slidably supporting the staples, a cover hinged to one side of the magazine body and being longitudinally movable between locked and released positions with and from the forward discharge end of the magazine, spring means biasing said cover toward the forward end of the magazine into locking engagement therewith and when retracted therefrom serving to open the cover, a staple follower slidable along the track, a follower pull rod connected to the follower to pull the follower rearwardly, said follower being retractable to the rear end of the magazine and engageable with the cover when so retracted to move the cover rearwardly against the spring bias to free the cover from its engagement with the forward end of the magazine whereby the cover will be automatically opened under the action of its spring when retracted therefrom serving to open the cover, a a

staple*follower slidable along the track, a follower pull rod connected to the follower to pull the follower rearwardy, said follower being retractable to the rear end of the magazine and engageable with the cover'when so retracted to move the cover rearwardly against the spring I bias to-free the cover from its engagement withthe'forv ward end of the magazine whereby the cover will be automatically opened under the action of its spring upon the retraction of the follower, said hinged cover upon being opened having a part that is engageable with said follower to hold the follower in its retracted position and a follower spring normally biasing the'follower'toward the i forward discharge end of the magazine, said follower pull rod being slidable through the follower to permit the return of thefollo-wer pull rod toits forward position without the follower. i 7

4. A magazine for discharging staples, comprising a body and a track for slidably supporting the staples, a cover hinged to one side of the body and being longitudinally movable between locked andreleasedpositions with *and from the forward discharge end of the magazine, spring means biasing said cover toward the forward end of the magazine into locking-engagement therewith and when retracted therefrom serving 'to open the cover,

I a staple follower slidable along the'track, a follower pull rod connected to the follower to pull the follower rearwardly, said follower being retractable to'the rear end of the magazine and engageable;with the' coverwhen follower overlying the track, a

said follower pull rod having an annular locking upon the retraction of the follower, said hinged cover upon being opened having a part that is engageable with said follower to hold the follower, in its retracted position, and a follower spring normally biasing the follower toward the forward discharge end of the magazine, said follower pull rod being slidable through the follower to permit the return of the follower pull rod to its forward position without the follower, said magazine having a hole in the rear end thereof and an O-ring retained in said hole through which the follower pull rod is slidable and by which it is retained in its forward position free of the follower, and said hole in the rear end of the magazine having a spring retaining cup therewithin abutting the O-ring to hold it in place within the hole, the rear end of said follower spring being seated in said retaining cup, groove for receiving the O-ring when the follower pull rod is in its forward position.

6.'In .a stapler, a handle having a forward cylinder portion and a depending rear leg portion, a staple magazine connected between the cylinder portion and the depending rear leg portion, said magazine comprising a track base, a staple track running along the base, a .cover hinged to one side of the trackbase, a combined compression and torsion spring biasing said cover toward the forward portion of the magazine for locking engagement with said forward portion and when released therefrom serving to open the cover to its open position, a staple follower pull rod c0nnected to the follower to pull the follower rearwardly, a follower spring surrounding'the pull rod for normally biasing the follower and the staples upon said track toward the forward portion of said magazine, said follower being retractable to therear end of the magazine and engageable thereat with the cover to move the cover rearwardly again st'the spring bias to free the cover from the said forward portion whereby the cover will be auto matically opened under the action of its hinge spring upon the retraction of the follower.

so retracted to move th'ecover rearwardly against the 7 spring bias to free'the cover from-its engagementwith the forward end of the magazine whereby the cover-"will be 7. In a stapler as defined in claim 6, and said cover having a lug that as the cover is opened is engageable with the follower when in its retracted position to retain the'follower thereat so as to permit the loading of the a magazine with staples, said follower being automatically 7 released from the cover lug as themagazine cover is closed.

8. In a stapler as defined in claim 7, said pull rod being slidable through the rear end of said magazine and serving to retract the follower to its retracted position for engagement by the cover lug, said pull rod being slidably connected to said follower to permit forward movement of the pull rod to its forward position free of the follower.

9. In a stapler as defined in claim 8, and said pull rod having an .annular groove, said magazine having 'an elastic O-ring expansible about the pull rod and seatable in the annular groove on the pull rod to retain the pull rod in its forward position.

10. In a stapler, a handle body having a forward cylinder portion and a depending rear leg portion, said cylinder portion having a driving blade depending therefrom, a staple magazine connected between the cylinder and the said depending leg portion, said cylinder portion having a transversely-extending slot, a guide plate carried on the staple magazine and having its upper end extending into said transverse slot, said guide plate having a discharge opening for the staples, a cover plate extending into said transverse slot and forwardly of the guide plate, means forcing the staples through the discharge opening so as to press the foremost staple against the cover plate, the said driving blade being slidable between the cover and guide plates across the discharge opening for engaging the foremost staple, and set screw means on the cylinder portion and extending into said transverse slot for releasable securing the cover plate within the transverse slot and against the guide plate, and said cover plate when released being movable upwardly in said transverse slot, and means detachably connecting the cover plate at its lower end to the guide plate and being releasable therefrom upon upward movement of the cover plate. 11. In a stapler as defined in claim 10, and said means for releasably securing the lower end of the cover plate to the lower end of the guide plate comprising laterallyspaced lugs on the guide plate, said lugs respectively having inner beveled faces, said cover plate having beveled edges engageable with the inner beveled faces of the References Cited in the file of this patent UNITED STATES PATENTS 2,001,104 Maynard May 14, 1935 2,733,440 Jenny Feb. 7, 1956 2,801,417 Jenny Aug. 6, 1957 2,817,839 'Skrebba Dec. 31, 1957 2,857,596 Allen Oct. 28, 1958 FOREIGN PATENTS 238,341 Switzerland Oct. 16, 1945 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,041,614 July 3, 1962- Marcel P. D'Haem et a1.

It is hereby certified that error appears in the above numbered petent requiring correction and that the said Letters Patent should read as corrected below Column 8, line 16, strike out "magazine".

Signed and sealed this 28th day of September 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J BRENNE Ailcsting Officer Commissioner of Fate: 

